Sigma or Summation function in Excel

Question

Given a value (in a cell), calculate a formula like this:

Ʃ(3i+1) for i from 0 to the value specified in the cell.

SUM(), SERIESSUM() are not suitable in thi

Answer 1

Demo as below graph:

Write in B2 Cell with =SUM(3*(ROW(INDIRECT(CONCATENATE("1:",A2+1)))-1)+1) then press Ctrl + Shift + Enter.